Do they exist?
Yes
http://www.kadee.com/conv/pdf/b52.pdf
let us see
first are Bachmann couplers
http://www.trainsetsonly.com/page/TSO/CTGY/COUPLE-BACH-HO
then you got kadee
http://www.trainsetsonly.com/page/TSO/CTGY/COUPLE-KADEE-HO
McHenry
http://www.trainsetsonly.com/page/TSO/CTGY/COUPLE-MCH-HO